In recent years, an ultrasonic diagnostic device that collects volume data by using an ultrasonic probe capable of scanning a subject three-dimensionally has been put to practical use. In such an ultrasonic diagnostic device, rendering is performed with respect to the collected volume data with various kinds of rendering methods. For example, as a rendering method used in the ultrasonic diagnostic device, a volume rendering method of generating a two-dimensional image that reflects three-dimensional information has been known.
In recent years, a rendering method referred to as “global illumination” has been also known. The global illumination is a method of acquiring a more realistic image by rendering volume data, while taking into consideration propagation (such as attenuation or reflection) of light in a real space.